This obstructive force of the anthropomorphic interpretation of phenomena is by no means the same in all lines of activity. The difficulty, at least in the earlier days, seems to be greatest along those lines of craft where the workman has to do with the mechanical, inanimate forces--the simplest in point of brute concreteness and the least amenable to a consistent interpretation in animistic terms. While man is conventionally distinguished from brute creation as a “tool-using animal,” his early progress in the devising and use of efficient tools, taking the word in its native sense, seems to have gone forward very slowly, both absolutely and as contrasted with those lines of workmanship in which he could carry his point by manual dexterity unaided by cunningly devised implements and mechanical contrivances;[32] and still more striking is the contrast between the incredibly slow and blindfold advance of the savage culture shown in the sequence of those typical stone implements which serve conventionally as land-marks of the early technology, on the one hand, and the concomitant achievements of the same stone-age peoples in the domestication and use of plants and animals on the other hand. No man can offer a confident conjecture as to how long a time and what a volume of experience was taken up in the growth of technological insight and proficiency up to the point when the neolithic period begins in European prehistory. In point of duration it has been found convenient to count it up roughly in units of geologic time, where a thousand years are as a day. Attempts to reduce it to such units as centuries or millennia have hitherto not come to anything appreciable. In the present state of information on this head it is doubtless a safe conjecture that the interval between the beginning of the human era and the close of palæolithic time, say in Europe or within the cultural sequence in which Europe belongs, is to be taken as some multiple of the interval that has elapsed from the beginning of the neolithic culture in Europe to the present;[33] and the neolithic period itself was in its turn no doubt of longer duration than the history of Europe since the bronze first came in.[34] The series of stone implements recovered from palæolithic deposits show the utmost reach of palæolithic technology on its mechanical side, in the way of workmanlike mastery of brute matter simply; for these implements are the tools of the tool-makers of that technological era. They indicate the ultimate terms of the technological situation on the mechanical side, for the craftsman working in more perishable materials could go no farther than these primary elements of the technological equipment would carry him.